Reactor



Patented Nov. 9, 1943 UNITED STATES PATENT OFFICE 8 Claims.

This invention relates to new and useful im- ,provements in reactors andhas particular relation to a construction of reactor and to a method ofmaking the same.

The objects and advantages of the invention will become apparent from aconsideration of the following detailed description taken in connec;

tion with the accompanying drawing wherein a satisfactory embodiment ofthe invention is shown. However, it is to be understood that theinvention is not limited to the details disclosed but includes all suchvariations and modifications as fall within the spirit of the inventionandthe scope of the appended claims.

In the drawing:

Fig. 1 is a front elevational view illustrating the reactor of theinvention;

Fig. 2 is an end elevatlonal view of the same;

Fig. 3 is a plan view suggesting the manner in which the laminations ofthe reactor are blanked from a strip;

Fig. 4 is a plan view of a keeper lamination as blanked from the strip;

Fig. 5 is a plan-view showing the operationof I pressing a stack of thekeeper laminations to keeper ii. The thickness of the spacers thus usedhas depended on the impedance desired in the reactor being manufactured.These spacers are not dependable as very slight variations in thespacing of the body II and keeper l2 have very material effects on theimpedance of the completed reactor and for this reason the production ofreactors all uniform, one to the next, has not heretofore been attained.

In addition the use of the spacers results in the formation of a strongstray held outside the body of the reactor, about the spacers from thebody H to the end of the keeper l2. Thus the described type of reactorif put in a magnetic metal case, or put near iron or other magneticmaterial, causes a vibration and an annoying hum or noise. When put in amagnetic metal case, having a close fit, the above mentioned magneticleakage passes through such case, bypassing the spacers, and changingthe characteristics of the reactor.

According to the present invention reactors of identical impedance maybe made in large quanshape and finish them in accordance with theinvention; and I Fig-. 6 is an end view of the upper portion of saidstack of laminations after being pressed. Referring in detail to thedrawing the reactor of the invention is generally designated I0 andcomprises a body ll of E-shaped laminations and a keeper I! of bar-likelaminations. Generally the laminations are punched and out from stripstock of the proper width as suggested in Fig. 3 wherein at I! is showna strip of magnetic material suitable for use in a reactor.

Pieces H (see Fig. 4) are punched from strip l3 leaving slots a, andthereafter the strip is severed as along thedotted line I, cutting oilfrom the strip an E lamination it. Then the strip is fed forward,severed along the dotted a a keeper and a coil has been mounted on thecenter leg of the body II and paper or the like interposed between thefree ends of the outer legs of the E laminations of the body and thetitles at relatively low cost. In addition in the reactors of theinvention the strong stray field is eliminated whereby a greater rangeof materials are usable for the purpose of mounting or secreting thereactors. I assemble the E-shape laminations in any or the usual mannerto provide body H and mount the proper coil I! on the center leg of suchassembled body in any or the usual manner.

The desired number of laminations H are as-i sembled into side-by-siderelation and clamped, together. Then these assembled laminations aretreated in a press. Fig. 5 suggests this operation and in that Fig. 19indicates a die having a forwardly projecting portion 20 and flatsurfaces 2! at each end of such portion. Portion 20 is raised an amountdepending on the impedance factor of the reactor being manufactured andis usually ,raised from two to twenty-five thousandths of an inch. I 3

Di I8 is mounted in a press (not shown) the work holder of which is madeto receive the laminations H of a complete keeper l2 and is reiieved inits portion opposite the mid-portion of the inner edge of suchlaminations. By any suitable means the laminations are held tightlyagainst one another with their edges aligned. As the press is closed theraised die portion 20 engages the mid-portions of the keeper laminationsand depresses such portions as at 22 in Figs. 1 and 5.

Since the laminations are held tightly against lateral displacement themetal displaced by the die is forced outwardly at the rear edges of thelaminations as at 23 in Figs. 1 and 2. In this pressing operation theend portions 2| of the die engage the surface portions 24 of the keeperat the opposite ends of the depression 22 with the result that burs andthe like are pressed flat and the surface portions 24 of the keeper areleft smooth and flat. As an alternative method the individuallaminations may have the depressions pressed therein and thereafter thelaminations are assembled with the depressions aligned.

Thereafter the keeper I2 is assembled on the body H with the surfaceportions 24 of the keeper tight and flat against the free ends of theoutside legs 25 and 26 of the body as at 21 in Fig. 1. This assemblywith the depression 22 facing the free end of the center leg of the bodyleaves a space between the keeper and such center leg. Such spacedetermines the impedance of the reactor. Therefore, as, through the useof the die, the depth of the depression 22 may be made exactly the depthdesired the impedance of the reactor may be accurately determined andduplicate reactors, or reactors having duplicate impedance factors, maybe produced at relatively low cost.

With the described construction the surface portions of the keeper areflat against the free ends of the outside legs of the body ll making forefliciency and uniformity in the reactor. There is no by-passing of themagnetic circuit about any insulator or spacer and the magnetic circuitis completely closed and the flow is entirely within the laminations.Therefore the reactor of the invention may be placed in a case ofmagnetic material without any material change in the characteristics. ofthe reactor and with a minimized vibration or noise resulting in thecomplete device.

The reactors of the invention may be made at low cost in quantity and ofuniform impedance and they will retain their predeterminedcharacteristics during long use. Where paper or the like is used as aspacer between the keeper and the body of the reactor the paper is notof uniform thickness and deteriorates in time, For these and otherreasons uniform results have not heretofore been obtained.

With the reactors of the invention a uniform structure is had anduniform results are obtained. The space between the center leg H and thekeeper I2 is dependent on the depth of the depression 22 and the latteris accurately controlled by the die H. In its operation, and as anincident thereto. the die smooths any burs or the like on the surfaces24 of the keeper so that such surfaces, in the finished keeper, aresmooth and fully contact the ends of the legs 25 and 28 of the body inthe assembled reactor. The depression 22 being made by means of a die itwill be'the same in each keeper and is inexpensively made; It beunderstood that the invention is not limitedto impedance devicesincluding bodies of E laminations.

Having thus set forth the nature of my invention, what I claim is: I

1. In a reactor, a body of E-shaped laminations the legs of which. areof equal length and each provided with a flat free end, a coil about thecenter leg of said body, a laminated keeper on saidbodyand having andportions directly against-'the-.-free -ends of the outer" legs of thebody, and said keeper in its intermediate portion opposite-the centerleg of the body provided with a flat bottom recess of a predetermineddepth whereby such portion is spaced a predetermined distance from thefree end of the center leg of the body to determine the impedance of thereactor.

2. The method of making reactors of uniform impedance comprisingassemblying a body of E-shaped laminations the legs of which are ofequal length and each provided with a flat free end, assemblying anindependent keeper of barlike laminations, off-setting the intermediateportion of the keeper in the plane of the laminations thereof to providea flat bottomed depression in an edge of said keeper intermediate theends thereof without substantial change in the cross-sectional area andconfiguration of the keeper, and assemblying the keeper on the body withsaid depression facing and aligned with the free end of the center legof the body and with the end portions of the keeper beyond saiddepression in direct contact with the free ends of the outside legs ofthe body.

3. The method of making reactors of uniform impedance comprisingassemblying a body of E-shaped laminations the legs of which are ofequal length and each provided with a fiat free end, assemblying anindependent keeper of barlike laminations, off-setting the intermediateportion of the keeper in the plane of the laminations thereof to providea flat bottomed depression in an edge of said keeper intermediate theend portions thereof without substantial change in the cross-sectionalarea and configuration of the keeper through the use of a die,simultaneously with the forming of said depression bringing the dieagainst the portions of the keeper beyond the ends of such depression tosmooth such portions of the keeper, and assemblying the keeper on thebody with said depression facing and aligned with the center leg of thebody and with the smooth end portions of the keeper beyond saiddepression in direct contact with the free ends of the outer legs of thebody.

4. The method of making reactors of uniform impedance comprisingassemblying a body of E-shaped laminations the legs of which are ofequal length and each provided with a free flat end. assemblying anindependent keeper of bar-like laminations, forming a flat bottomeddepression in an edge portion of the keeper, and assemblying the keeperon the body with said depression facing and aligned with the free end ofthe center leg of the body and with the end portions of the keeperbeyond said depression in direct contact with the free ends of the outerlegs of the body.

5. A reactor including a laminated keeper of substantially uniformcross-sectional area and configuration throughout its length having arecess formed in an edge thereof a predetermined distance to determinethe impedance of the reactor.

6. A multipart reactor in which one of the parts comprises a stack oflaminations of substantially uniform cross-sectional area andconfiguration throughout their length recessed in an edge apredetermined distance to determine the impedance factor 01' thereactor.

7. The method of making reactors of uniform impedance comprisingassemblying a stack of laminations to form a reactor part, andoff-setting the intermediate portion of said part in the planes of thelaminations thereof to provide in one edge thereof a depression of apredetermined depth without substantially changing the cross-sectionalarea of the part, and assemblying said part with other reactor parts toform a complete device with the depth of such depression determining theimpedance factor of the reactor.

8. The method of making reactors of uniform impedance comprisingpressing similar depressions in the edges of iaminations withoutsubstantially changing the cross-sectional areas and configurations ofsaid laminations, assemblying the laminations into a stack comprising areactor part with the depressions of the individual laminations inaligmnent, and then assemblying such part with other reactor parts toform a complete device with the depth of such depressions determiningthe impedance of the reactor.

EDWIN G. GAYNOR.

